T. Katoh

Present Status of the J-PARC Control System

The present status of the design and construction of the control system for Japan Proton Accelerator Research Complex (J-PARC) is given. J-PARC is a 3-stage accelerator complex with a 200MeV Linac, a 3GeV Rapid Cycling Synchrotron (RCS) and a 50GeV Main Ring synchrotron (MR). The accelerators are under construction jointly by Japan Atomic Energy Research Institute (JAERI) and KEK, High Energy Accelerator Research Organization. Linac and RCS are being constructed mainly by JAERI and MR is mainly by KEK. [1,2] And the control systems for Linac and RCS [17] are constructed mainly by JAERI and that of MR is done mainly by KEK. [3] Commissioning of Linac, RCS and MR are scheduled in September 2006, May 2007, and January 2008, respectively. There are three control systems under construction corresponding to three accelerators. These three control systems will be operated from one central control room when each control system is completed construction. We chose Experimental Physics and Industrial System (EPICS) [4] as the software environment so that three control systems can be unified easily to single control system. J-PARC control system has the three-layer standard model architecture for accelerator controls that is very common in the EPICS world. We have chosen the standard network protocol TCP/IP and UDP/IP as the J-PARC standard field-bus used to connect interface units that links accelerator component to the control system.

The TRISTAN control system

The 8 GeV accumulation ring and the 30 GeV main ring of TRISTAN, an accelerator-storage ring complex at KEK, are controlled by a highly computerized control system. Twenty-four minicomputers are linked by optical fiber cables to form an N-to-N token ring network. The transmission speed on the cables is 10 Mbps. From each minicomputer, a CAMAC serial highway extends to the controlled equipment. At present, twenty minicomputers are connected to the network and are used to control the accumulation ring. The software system is based on the NODAL language devised at the CERN SPS. The KEK NODAL system retains main features of the original NODAL: the interpretive scheme, the multi-computer programming facility, and the data-module concept. In addition, it has the following features: (1) fast execution due to the compiler-interpreter method, (2) a multi-computer file system (3), a full-screen editing facility, and (4) a dynamic linkage scheme for data modules and NODAL functions. The accelerators are operated through five operator consoles, each of which is managed by one minicomputer in the network. An operator console contains two 20-inch high-resolution color graphic displays, a pair of touch-panels, and ten small TV monitors. One touch-panel is used to select a program and a piece of equipment to be controlled; the other is used mainly to perform the console actions.

KEKB accelerator control system

The KEKB accelerator control system including a control computer system, a timing distribution system, and a safety control system are described. KEKB accelerators were installed in the same tunnel where the TRISTAN accelerator was. There were some constraints due to the reused equipment. The control system is based on Experimental Physics and Industrial Control System (EPICS). In order to reduce the cost and labor for constructing the KEKB control system, as many CAMAC modules as possible are used again. The guiding principles of the KEKB control computer system are as follows: use EPICS as the controls environment, provide a two-language system for developing application programs, use VMEbus as frontend computers as a consequence of EPICS, use standard buses, such as CAMAC, GPIB, VXIbus, ARCNET, RS-232 as field buses and use ergonomic equipment for operators and scientists. On the software side, interpretive Python and SAD languages are used for coding application programs. The purpose of the radiation safety system is to protect personnel from radiation hazards. It consists of an access control system and a beam interlock system. The access control system protects people from strong radiation inside the accelerator tunnel due to an intense beam, by controlling access to the beamline area. On the other hand, the beam interlock system prevents people from radiation exposure by interlocking the beam operation. For the convenience of accelerator operation and access control, the region covered by the safety system is divided into three major access control areas: the KEKB area, the PF-AR area, and the beam-transport (BT) area. The KEKB control system required a new timing system to match a low longitudinal acceptance due to a low-alpha machine. This timing system is based on a frequency divider/multiply technique and a digital delay technique. The RF frequency of the KEKB rings and that of the injector Linac are locked with a common divisor frequency. The common divisor frequency determines the injection timing. The RF bucket selection system is also described. r 2002 Elsevier Science B.V. All rights reserved.

KEK NODAL System

The KEK NODAL system, which is based on the NODAL devised at the CERN SPS, works on an optical-fiber token ring network of twenty-four minicomputers (Hitachi HIDIC 80s) to control the TRISTAN accelerator complex, now being constructed at KEK. KEK NODAL retains main features of the original NODAL: the interpreting scheme, the multi-computer programming facility, and the data-module concept. In addition, it has the following characteristics: (1) fast execution due to the compiler-interpreter method, (2) a multicomputer file system, (3) a full-screen editing facility, and (4) a dynamic linkage scheme of data modules and NODAL functions. The structure of the KEK NODAL system under PMS, a real-time multitasking operating system of HIDIC 80, is described; the NODAL file system is also explained.

Man-Machine Interface of Tristan

This report describes a console system which is the essence of man-machine interface used to operate TRISTAN. Ergonomic design and its implementation has been done in construction of the TRISTAN Central Control Room (TCCR) and Operators Console (OPC). The environment of the console is designed to minimize fatigue, eyestrain and discomfort by optimizing light fixtures, minimizing noises made by fans or footsteps and harmonizing colors and brightness throughout the control room. The OPC is composed of a special supervisory console at the center and five identical standard consoles. The difference between the two types is that hard-wired switches which manipulate beam gates and related equipments to assure the safety of personnel are mounted only on the former console. The safety system is based on the hardware techniques similar to those have been accepted for the control of critical industrial installations. Each of the consoles contains ten color TV monitors, two high resolution graphic display monitors and two touch-panels with color character display monitors. Each console is managed by a minicomputer of the TRISTAN control computer network. The graphic displays are connected directly to the computer. The touchpanels and the corresponding character video RAM modules are through CAMAC serial highway.

Characteristics of the TRISTAN control computer network

Abstract Twenty-four minicomputers forming an N -to- N token-ring network control the TRISTAN accelerator complex. The computers are linked by optical fiber cables with 10 Mbps transmission speed. The software system is based on NODAL, a multicomputer interpretive language developed at the CERN SPS. The high-level services offered to the users of the network are remote execution by the EXEC, EXEC-P and IMEX commands of NODAL and uniform file access throughout the system. The network software was designed to achieve the fast response of the EXEC command. The performance of the network is also reported. Tasks that overload the minicomputers are processed on the KEK central computers. One minicomputer in the network serves as a gateway to KEKNET, which connects the minicomputer network and the central computers. The communication with the central computers is managed within the framework of the KEK NODAL system. NODAL programs communicate with the central computers calling NODAL functions; functions for exchanging data between a data set on the central computers and a NODAL variable, submitting a batch job to the central computers, checking the status of the submitted job, etc. are prepared.